Geospatial representation of data-less map areas

ABSTRACT

Some embodiments provide a non-transitory machine-readable medium that stores a mapping application which when executed on a device by at least one processing unit renders views of a three-dimensional (3D) map. The mapping application requests a first set of map tiles associated with a portion of the 3D map. In response to the request, the mapping application receives a second set of map tiles associated with portion of the 3D map. The mapping application identifies a third set of map tiles included in the first set of map tiles but not included in the second set of map tiles. For each map tile in the third set of map tiles, the mapping application generates a replacement map tile comprising geospatial data. The mapping application renders the portion of the 3D map based on the second set of map tiles and the set of replacement map tiles.

CLAIM OF BENEFIT TO PRIOR APPLICATIONS

This application claims the benefit of U.S. Provisional PatentApplication 61/656,032, filed Jun. 6, 2012; U.S. Provisional PatentApplication 61/656,043, filed Jun. 6, 2012; U.S. Provisional PatentApplication 61/657,880, filed Jun. 10, 2012; and U.S. Provisional PatentApplication 61/699,803, filed Sep. 11, 2012. U.S. Provisional PatentApplications 61/656,032, 61/656,043, 61/657,880, and 61/699,803 areincorporated herein by reference.

BACKGROUND

Many computing devices (e.g., tablet computing devices, smartphones,laptops, etc.) today can access information from a variety of differentlocations. For example, many devices are capable of communicatingwirelessly and, thus, can access information at home, at work, at publichotspots, at airports, on airplanes, etc.

Users of these devices often install or use a native mapping applicationfor viewing maps. Typically, the mapping application utilizes datastored remotely (e.g., a server). When the devices can connect to thedata (e.g., via the Internet), the user may view the map. However, thedevices cannot access the data, the mapping application is unable todisplay portions of the map, or sometimes the entire map altogether.

BRIEF SUMMARY

For a mapping application, some embodiments of the invention provide anovel method for rendering views of a three-dimensional (3D) map. Insome embodiments, when rendering a view of the 3D map, the methodidentifies a portion of the 3D map to use for rendering the view. Forthe identified portion of the 3D map, the method of some embodimentsidentifies (1) a set of sections of the 3D map for which data isunavailable (also referred to as data-less sections) and (2) a set ofsections of the map view for which data is available. Based on sectionsfor which data is available, the method generates for the data-lesssections filler sections that include geospatial information. In someembodiments, the method fills the data-less sections with thecorresponding filler section. The method of some embodiments thenrenders the view of the 3D map.

The preceding Summary is intended to serve as a brief introduction tosome embodiments of the invention. It is not meant to be an introductionor overview of all inventive subject matter disclosed in this document.The Detailed Description that follows and the Drawings that are referredto in the Detailed Description will further describe the embodimentsdescribed in the Summary as well as other embodiments. Accordingly, tounderstand all the embodiments described by this document, a full reviewof the Summary, Detailed Description and the Drawings is needed.Moreover, the claimed subject matters are not to be limited by theillustrative details in the Summary, Detailed Description and theDrawing, but rather are to be defined by the appended claims, becausethe claimed subject matters can be embodied in other specific formswithout departing from the spirit of the subject matters.

BRIEF DESCRIPTION OF THE DRAWINGS

The novel features of the invention are set forth in the appendedclaims. However, for purposes of explanation, several embodiments of theinvention are set forth in the following figures.

FIG. 1 conceptually illustrates a mapping application of someembodiments that generates geospatial map tiles for unavailable maptiles.

FIG. 2 conceptually illustrates a view of a 3D map that includesgeospatial information after a panning operation according to someembodiments of the invention.

FIG. 3 conceptually illustrates a view of a 3D map that includesgeospatial information after a zoom-out operation according to someembodiments of the invention.

FIG. 4 conceptually illustrates a view of a 3D map that includesgeospatial information after a zoom-in operation according to someembodiments of the invention.

FIG. 5 conceptually illustrates a 3D perspective view of a 3D map thatincludes geospatial information after a 3D panning operation accordingto some embodiments of the invention.

FIG. 6 conceptually illustrates an example presentation of geospatialinformation according to some embodiments of the invention.

FIG. 7 conceptually illustrates another example presentation ofgeospatial information according to some embodiments of the invention.

FIG. 8 conceptually illustrates another example presentation ofgeospatial information according to some embodiments of the invention.

FIG. 9 conceptually illustrates a process of some embodiments forproviding geospatial information for unavailable map data.

FIG. 10 conceptually illustrates a processing pipeline performed by themapping application of some embodiments in order to render a map fordisplay at the client device.

FIG. 11 conceptually illustrates an example of an architecture of amobile computing device of some embodiments.

FIG. 12 conceptually illustrates an example of an electronic system withwhich some embodiments of the invention are implemented.

FIG. 13 conceptually illustrates an electronic device with which someembodiments of the invention are implemented.

DETAILED DESCRIPTION

In the following detailed description of the invention, numerousdetails, examples, and embodiments of the invention are set forth anddescribed. However, it will be clear and apparent to one skilled in theart that the invention is not limited to the embodiments set forth andthat the invention may be practiced without some of the specific detailsand examples discussed.

For a mapping application, some embodiments of the invention provide anovel method for rendering views of a three-dimensional (3D) map. Insome embodiments, when rendering a view of the 3D map, the methodidentifies a portion of the 3D map to use for rendering the view. Forthe identified portion of the 3D map, the method of some embodimentsidentifies (1) a set of sections of the 3D map for which data isunavailable (also referred to as data-less sections) and (2) a set ofsections of the map view for which data is available. Based on sectionsfor which data is available, the method generates for the data-lesssections filler sections that include geospatial information. In someembodiments, the method fills the data-less sections with thecorresponding filler section. The method of some embodiments thenrenders the view of the 3D map.

FIG. 1 conceptually illustrates a mapping application 110 of someembodiments that generates geospatial map tiles for unavailable maptiles. As shown, FIG. 1 illustrates the mapping application 110, aportion of a 3D map 105, a virtual camera 100, a map tile provider 120,and a 3D map view 150 of the 3D map 105.

In some embodiments, the mapping application 110 generates views of a 3Dmap for display on a device on which the mapping application 110 isoperating. In this example, the mapping application 110 generates the 3Dmap view 150 of the 3D map 105. As shown, the 3D map 105 includes twobuildings and two roads that form a T-junction.

The virtual camera 100 is a conceptualization of the position in the 3Dmap 105 from which the mapping application 110 renders the 3D map view150. As illustrated in FIG. 1, the mapping application 110 sends arequest 165 for a view of the 3D map 105 to render, and in response, thevirtual camera 100 sends the mapping application 110 a field of view 140(e.g., a viewing frustum) of the 3D map 105. Based on the field of view140, the mapping application 110 identifies a set of map tiles 130necessary to render the 3D map 105. The mapping application 110 thensends a tile list 125 of the set of map tiles 130 to the map tileprovider 120.

The map tile provider 120 is responsible for retrieving map tilesrequested by the mapping application 110. In some embodiments, the maptile provider 120 maintains a cache of map tiles (e.g., recentlyrequested map tiles, often requested map tiles, etc.). Thus, the maptile provider 120 checks the cache of map tiles and retrieves any of therequested map tiles 130 that are available in the cache. For therequested map tiles 130 that are not available in the cache, the maptile provider 120 of some embodiments requests those tiles from a mapservice, such as the one described below by reference to FIG. 13.

In some instances, the map tile provider 120 cannot retrieve some of therequested map tiles 130. For example, the device on which the mappingapplication 110 is operating might not have a data connection becausethe cellular coverage of the area where the device is located has littleor no coverage. After a defined amount of time or a defined number ofattempts to retrieve the map tiles 130, the map tile provider 120returns to the mapping application 110 the requested map tiles 130 thatthe map tile provider 120 was able to retrieve.

When the mapping application 110 receives the set of map tiles 130 fromthe map tile provider 120, the mapping application 110 renders the 3Dmap view 150. Details of rendering views of a 3D map are discussed belowby reference to FIG. 10. In cases where the mapping application does notreceive all of the requested map tiles 130, the mapping application 110dynamically generates geospatial map tiles in place of the unavailablemap tiles. As shown in this example, the mapping application 110 did notreceive the map tiles 135 from the map tile provider 120. Thus, themapping application 110 generates geospatial map tiles 160 to substitutefor the unavailable map tiles 135 and then renders the map view 150 fordisplay on the device.

As shown in FIG. 1, the sections of the 3D map 105 that correspond tothe unavailable map tiles 135 are filled in by the geospatial map tiles160. In some embodiments, the geospatial map tiles 160 includegeospatial information to allow a user to visually determine distancesin the 3D map view 150 in an easy and informative manner.

While FIG. 1 shows the map tile provider 120 and the mapping application110 as separate modules, in some embodiments, the map tile provider 120and the mapping application 110 are implemented as a single module thatperforms the functions of each of the modules while, in someembodiments, the map tile provider 120 and the mapping application 110are implemented as separate applications.

Several figures (e.g., FIGS. 1 and 5) described above and below in thisapplication show map views of a 3D map without user interface (UI)controls for purposes of simplicity and explanation. One of ordinaryskill in the art will realize that the mapping application of someembodiments renders the map views with UI controls. For instance, insome embodiments, the mapping application renders the map views with theUI controls described below by reference to FIGS. 2-4.

Several more detailed embodiments of the invention are described in thesections below. Section I provides a description of several examples ofoperations on a 3D map that result in unavailable map tiles. Next,Section II conceptually describes an image processing pipeline of themapping application of some embodiments. Section III follows this with adescription of several electronic systems that implement someembodiments of the invention. Finally, Section IV describes a mapservice environment in which the mapping application of some embodimentsoperates.

I. Geospatial Map Tiles

As described above, in some embodiments, the mapping applicationprovides a feature that presents geospatial information for sections ofa 3D map for which map data is unavailable. The following sectiondescribes several exemplary scenarios in which the mapping applicationof some embodiments may generate geospatial map tiles for unavailablemap tiles.

FIG. 2 conceptually illustrates a view of a 3D map with geospatial maptiles after a panning operation according to some embodiments of theinvention. Specifically, FIG. 2 conceptually illustrates a GUI 200 atthree different stages 205-215 of a panning operation.

As shown in the first stage 205, the GUI 200 includes several userinterface (UI) controls and a two-dimensional (2D) view 220 of a 3D map(also referred to as an orthographic view or a top-down view). The 2Dview 220 shows several streets running along a horizontal orperpendicular direction. In addition, the GUI 200 includes a signalstrength icon in the top right corner that represents the strength of aconnection (e.g., measured in decibel-milliwatt (dBm), etc.) between adevice on which the mapping application is running and a network (e.g.,a cellular network) within which the device is operating. In thisexample, the device does not have a connection with a network, asindicated by the signal strength icon completely grayed-out.

The second stage 210 illustrates a user providing input (e.g., a swipegesture) to pan the 2D view 220 of the 3D map. Specifically, the user istouching a finger on a touchscreen of the device displaying the 2D view220 and dragging the finger in a downward direction. In someembodiments, panning the 3D map (e.g., a defined distance) causes themapping application to retrieve map tiles to render the new view of the3D map to which the 3D map is panned. For this example, the view of the3D map to which the user has panned causes the mapping application toretrieve map tiles for the new view of the 3D map.

In the third stage 215, the GUI 200 is displaying a 2D view 225 of the3D map. As shown, the 2D view 225 illustrates the top portion of the 2Dview 220 that was moved down as a result of the panning operation and aset of geospatial map tiles 230 above the top portion of the 2D view220. To render the new portion of the 3D map in the 2D view 225 (i.e.the top section of the 2D view 225), the mapping application requestedmap tiles for the new portion of the 3D map. As noted above, in thisexample, the device does not have a connection with a network. Thus, thesections of the 2D view 225 at which the set of geospatial map tiles 230are located represent map tiles that were not unavailable. The mappingapplication in this example generated and rendered the 2D view 225 withthe set of geospatial map tiles 230.

Different embodiments use different techniques to generate geospatialmap tiles. For example, the mapping application of some embodiments usesany of the techniques described above and below by reference to FIGS. 1,9, and 10). Additionally, the mapping application in this examplerenders each geospatial map tile 230 with a bolding of the border and adistance indicator (200 feet in this example). The third stage 215 alsoshows that the mapping application rendered the distance indicators inthe geospatial map tiles 230 in an alternating fashion—alternatingbetween a horizontal distance indicator and a vertical distanceindicator.

FIG. 3 conceptually illustrates a view of a 3D map with geospatial maptiles after a zoom-out operation according to some embodiments of theinvention. In particular, FIG. 3 conceptually illustrates the GUI 200 atthree different stages 305-315 of a zoom-out operation.

The first stage 305 is similar to the first stage 205 described above byreference to FIG. 2. The GUI 200 at this stage 305 shows several UIcontrols and the 2D view 220 of the 3D map, which shows several streetsrunning along a horizontal or perpendicular direction. However, insteadof displaying the signal strength as indicating no signal, the signalstrength icon in this example has one bar highlighted and the restgrayed-out to indicate that the device has a weak connection with thenetwork.

The second stage 310 shows a user providing input (e.g., a pinchgesture) to zoom out from the 2D view 220 of the 3D map. In particular,the user is touching two fingers on the touchscreen of the devicedisplaying the 2D view 220 and dragging the fingers closer together. Insome embodiments, zooming out a defined amount of zoom levels (e.g., 1zoom level, 3 zoom levels, etc.) from the 3D map causes the mappingapplication to retrieve a new set of map tiles to render the zoomed-outview of the 3D map. In this example, the user has provided input to zoomout past the defined amount of zoom levels from the 2D view 220. In thisexample, the view of the 3D map to which the user has zoomed out causesthe mapping application to retrieve map tiles for the new view of the 3Dmap.

The third stage 315 shows the GUI 200 displaying a 2D view 325 of the 3Dmap. As illustrated, the 2D view 325 shows a portion of a zoomed-outview of the 2D view 220 and a set of geospatial map tiles 330. Themapping application renders the zoomed-out view of the 3D map byrequesting map tiles for the 3D map at the new zoom level. As mentionedabove, in this example, the connection between the device and thenetwork is weak. As such, the sections of the 2D view 325 at which theset of geospatial map tiles 330 are located represent map tiles thatwere not unavailable, which caused the mapping application to generateand render the 2D view 325 with the set of geospatial map tiles 330.

As shown, the mapping application rendered each of the geospatial maptiles 330 with a bolding of the border and a distance indicator (500feet in this example). The third stage 315 also shows that the mappingapplication rendered the distance indicators in the geospatial map tiles330 in a similar alternating manner as described above by reference toFIG. 2.

FIG. 3 illustrates a situation where the mapping application providesgeospatial map tiles when a 3D map is zoomed out. In some embodiments, azoom-in operation causes the mapping application to present geospatialmap tiles. FIG. 4 conceptually illustrates a view of a 3D map withgeospatial map tiles after a zoom-in operation according to someembodiments of the invention. More specifically, FIG. 4 conceptuallyillustrates the GUI 200 at three different stages 405-415 of a zoom-inoperation.

The first stage 405 is the same as the first stage 305 described aboveby reference to FIG. 3. That is, the GUI 200 is displaying several UIcontrols and the 2D view 220 of the 3D map and the signal strength iconhas one bar highlighted to indicate that the device has a weakconnection with the network.

In the second stage 410, the GUI 200 illustrates a user providing input(e.g., a spread gesture) to zoom into the 2D view 220 of the 3D map.Specifically, the user is touching two fingers on the touchscreen of thedevice displaying the 2D view 220 and dragging the fingers fartherapart. In some embodiments, zooming in a defined amount of zoom levels(e.g., 1 zoom level, 2 zoom levels, etc.) into the 3D map causes themapping application to retrieve a new set of map tiles to render thezoomed-in view of the 3D map. For this example, the user has providedinput to zoom in past the defined amount of zoom levels into the 2D view220. The view of the 3D map to which the user has zoomed into causes themapping application for this example to retrieve map tiles for the newview of the 3D map.

The third stage 415 illustrates the GUI 200 displaying a 2D view 425 ofthe 3D map. The 2D view 425 shows a portion of a zoomed-in view of the2D view 220 and a set of geospatial map tiles 430. The mappingapplication requests map tiles for the 3D map at the new zoom level inorder to render the zoomed-in view of the 3D map. As described above,the connection between the device and the network is weak for thisexample. Accordingly, the sections of the 2D view 425 at which the setof geospatial map tiles 430 are located represent map tiles that werenot unavailable. This caused the mapping application to generate andrender the 2D view 425 with the set of geospatial map tiles 430.

The third stage 415 shows that the mapping application rendered each ofthe geospatial map tiles 430 with a bolding of the border and a distanceindicator (100 feet in this example). In addition, the third stage 415illustrates that the mapping application rendered the distanceindicators in the geospatial map tiles 430 in a similar alternatingmanner as described above by reference to FIG. 2.

The above-described FIGS. 2-4 show examples of providing geospatialinformation for unavailable map tiles when the mapping application ofsome embodiments is viewing a 3D map from a 2D orthographic view.Details of operations performed by mapping applications when viewing a3D map from a 2D orthographic view are described in concurrently filedU.S. patent application Ser. No. ______, with attorney docket numberAPLE.P0423, entitled “Problem Reporting in Maps”; and concurrently filedU.S. patent application Ser. No. ______, with attorney docket numberAPLE.P0403, entitled “Virtual Camera for 3D Maps”. U.S. patentapplications Ser. No. ______, with attorney docket numbers APLE.P0423and APLE.P0403, are incorporated herein by reference. In someembodiments, the mapping application also provides geospatialinformation for a 3D map from a 3D perspective view.

FIG. 5 conceptually illustrates a 3D perspective view of a 3D map withgeospatial information after a 3D panning operation according to someembodiments of the invention. Specifically, FIG. 5 conceptuallyillustrates two different stages 505 and 510 of a panning operationwhile in a 3D perspective view of the 3D map.

The first stage 505 illustrates a 3D perspective view 515 of a 3D map.The 3D view 515 shows two buildings and two streets forming aT-junction. Addition, the first stage 505 shows a signal strength iconin the top right corner that represents the strength of a connection(e.g., measured in decibel-milliwatt (dBm), etc.) between a device onwhich the mapping application is running and a network (e.g., a cellularnetwork) within which the device is operating. For this example, thedevice has a weak connection with a network, as indicated by one barhighlighted and the remaining bars of the signal strength icongrayed-out.

The first stage 505 also illustrates a user providing input (e.g., aswipe gesture) to pan the 3D perspective view 515 of the 3D map. Inparticular, the user is touching a finger on a touchscreen of the devicedisplaying the 3D perspective view 515 and dragging the finger in a leftdirection. In some embodiments, panning the 3D map (e.g., a defineddistance) causes the mapping application to retrieve map tiles to renderthe new view of the 3D map to which the 3D map is panned. In thisexample, the view of the 3D map to which the user has panned causes themapping application to retrieve map tiles for the new view of the 3Dmap.

The second stage 510 illustrates a 3D perspective view 520 of the 3Dmap. As shown, the 3D perspective view 515 illustrates the right portionof the 3D perspective view 515 that was moved to the left as a result ofthe panning operation and a set of geospatial map tiles 525. To renderthe new portion of the 3D map in the 3D perspective view 520 (i.e. theright portion of the 3D perspective view 520), the mapping applicationrequested map tiles for the new portion of the 3D map. As mentionedabove, the device in this example has a weak connection with thenetwork, which prevented the mapping application from retrieving maptiles for the sections of the 3D perspective view 520 at which the setof geospatial map tiles 525 are located. For this example, the mappingapplication generated and rendered the 3D perspective view 520 with theset of geospatial map tiles 525 to fill in the unavailable map tiles. Inaddition, the mapping application in this example renders each of thegeospatial map tile 525 with a bolding of the border and a 3D calloutpointer at or near the center of the map tile. The 3D callout pointerindicates the distance (75 feet in this example) to the nearestavailable map tile in the 3D perspective view 520. Details of operationsperformed by the mapping application of some embodiments when viewing a3D map from a 3D perspective view are described in concurrently filedU.S. patent application Ser. No. ______, with attorney docket numberAPLE.P0423, entitled “Problem Reporting in Maps”; and concurrently filedU.S. patent application Ser. No. ______, with attorney docket numberAPLE.P0403, entitled “Virtual Camera for 3D Maps”.

The FIG. 1-5 described above illustrate operations that cause themapping application of some embodiments to generate geospatialinformation for rendering and displaying in a view of a 3D map. One ofordinary skill in the art will understand that other operations mightcause the mapping application to present geospatial information in viewsof the 3D map. Examples include rotate operations, search operations,navigation operations, or any other types of operation that causes themapping application to load new map tiles.

In addition, FIG. 1-5 show several different presentations of geospatialinformation. Different embodiments employ additional and/or differentpresentations of geospatial information in order to provide a user withuseful information for quickly determining distances. For instance, anyof the FIGS. 1-5 described above may use any of the followingpresentations of geospatial information in some embodiments.

FIG. 6 conceptually illustrates an example presentation of geospatialinformation according to some embodiments of the invention. Inparticular, FIG. 6 conceptually illustrates a single geospatial map tile600. As shown, the geospatial map tile 600 includes a set of grid linesthat represent longitude and latitude coordinates. The horizontal gridlines represent latitude coordinates 30°13′48″N, 30°13′47″N, and30°13′46″N. The distance between adjacent horizontal grid lines isequivalent to one second of a degree and differs depending on thelongitude coordinate value. Additionally, the vertical grid linesrepresent longitude coordinates 78°44′18″ W, 78°44′19″W, and 78°44′20″W.The distance between adjacent vertical grid lines is one second of adegree and depends on the latitude coordinate value.

FIG. 7 conceptually illustrates another example presentation ofgeospatial information according to some embodiments of the invention.Specially, FIG. 7 conceptually illustrates a single geospatial map tile700. As illustrated, the geospatial map tile 700 includes a two distancescales that indicate relative distances of 100 feet, 200 feet, and 300feet. One distance scale is displayed horizontally along the bottom ofthe geospatial map tile 700 while the other distance scale is displayedvertically along the left side of the geospatial map tile 700.

FIG. 8 conceptually illustrates another example presentation ofgeospatial information according to some embodiments of the invention.In particular, FIG. 8 conceptually illustrates a single geospatial maptile 800. As shown, the geospatial map tile 800 includes a set of gridlines that represent the closest distance to an available map tile. Forthis example, the geospatial map tile 800 is surrounded by available maptiles. As such, the distances indicated for the center grid lines is 40meters, and the distances indicated for the side grid lines is 20meters.

The FIGS. 6-8 explained above show examples of different presentationsof geospatial information in a geospatial map tile. One of ordinaryskill in the art will realize that geospatial information may bepresented in geospatial map tiles any number of different ways.

FIG. 9 conceptually illustrates a process of some embodiments forproviding geospatial information for unavailable map data. In someembodiments, the process 900 is performed by a mapping application(e.g., the ones described above by reference to FIGS. 1-5) that operateson a device with a display (e.g., a mobile computing device such as asmart phone or tablet computer) when the mapping application isrendering map views in a map viewing mode (e.g., a location browsingmode, a navigation mode, etc.). As mentioned above, the geospatialinformation in some embodiments provides spatially meaningfulrepresentations in sections of a map view that are not available (e.g.,no tiles available, the device cannot download or does not have accessto tiles, etc.).

The process 900 starts by receiving (at 910) a view of a map to render.As discussed above, the mapping application of some embodiments requests(e.g., from a virtual camera used to view the map) a map view to render.In some embodiments, the mapping application may request to render themap view in response to a user's input to adjust the current view of themap (e.g., rotate the map, zoom into the map, zoom out from the map, panthe map etc.) while, in some embodiments, the mapping applicationautomatically requests views of the map (e.g., when traversing anavigation route).

Next, the process 900 requests (at 920) from a map service tiles thatcorrespond to the portion of the map from which to render the view ofthe map for display on the device. In some embodiments, the tilescorrespond to grid sections of a map. The process 900 of someembodiments requests map tiles by identifying the portion of the mapfrom which to render the view of the map and requesting such map tiles.In some embodiments, the process 900 requests tiles automatically whilethe mapping application is in a map viewing mode.

The process 900 then receives (at 930) from the map service therequested map tiles to render the view of the map for display. Afterreceiving the map tiles, the process 900 determines (at 940) whether anyrequested map tiles are missing from the received map tiles (i.e., maptiles that are unavailable). Tiles may be missing for many reasons,including network interrupts, failure by a data server, if the map viewincludes areas for which no mapping data is available, the cellularcoverage of the area where the device on which the process 900 isexecuting is located has little or no coverage, etc. If the process 900determines that no map tiles are missing, then the process 900 proceedsto 960.

When the process 900 determines that there is one or more map tilesmissing, the process 900 generates (at 950) geospatial map tiles for themissing map tiles. To generate a geospatial map tile, the process 900 ofsome embodiments identifies a scale of the view of the map based on amap coordinate system associated with the map that is used for the viewof the map or distance information (e.g., metadata) included with thereceived map tiles. In some embodiments, the scale of the view of themap specifies the actual distances (e.g., real world distances) withrespect to the dimensions of the map tiles. The process 900 of differentembodiment generates different presentations of geospatial map tiles.For instance, in some embodiments, the process 900 generates any of thegeospatial map tiles described above by reference to FIGS. 1-8.

Finally, the process 900 renders (at 960) the view of the map fordisplay on the device. When geospatial map tiles have been generated forunavailable map tiles, the process 900 renders the view of the map thatincludes the available map tiles and the geospatial map tiles. When theprocess 900 receives all the requested map tiles, the process 900 simplyrenders the view of the map using the requested map tiles.

II. Image Processing Pipeline

FIG. 10 conceptually illustrates a processing pipeline 1000 performed bythe mapping application of some embodiments in order to render a map fordisplay at the client device (e.g., on the display of the clientdevice). As illustrated, the processing pipeline 1000 includes arequestor 1005, a loader/decompressor 1010, a tile processor 1050, ageospatial tile generator 1085, a set of mesh builders 1015, a tileprovider 1020, a virtual camera 1023, and a map rendering engine 1025.

The tile processor 1050 of some embodiments receives requests for maptiles from the mesh builders 1015 and performs a multiplexing operationbefore forwarding the requests. The mesh builders 1015, as will bedescribed below, identify existing map tiles (that are stored on amapping service server or in a cache on the device performing theprocessing pipeline 1000) needed to build their respective meshes. Insome embodiments, the map tiles are referenced as nodes of a quadtree.The tile processor acts as a multiplexer when multiple mesh buildersrequest the same tile. As the mesh builders request tiles, in someembodiments the tile processor 1050 stores these tiles in its queue.After either a particular period of time or after a particular number oftiles have been requested, the tile processor 1050 flushes the queue andsends the tile list to the loader/decompressor 1010.

In some instances, some of the requested map tiles may not be available(e.g., a user of the mapping application travels underground, through anarea without cellular coverage, etc.) and, thus, the tile processor 1050cannot complete the mesh builders 1015′ requests. In some embodiments,the tile processor 1050 sends a set of the available map tiles to thegeospatial tile generator 1085 and requests the geospatial tilegenerator 1085 to generate map tiles to use in place of the unavailablemap tiles.

The geospatial tile generator 1085 receives requests from the tileprocessor 1050 to generate map tiles. When the geospatial tile generator1085 receives such requests along with a set of available tiles (thatare part of the tiles requested by the mesh builders 1015), thegeospatial tile generator 1085 uses the data contained in the set ofavailable tiles to generate geospatial map tiles for the unavailable maptiles. Once the requested map tiles have been generated, the geospatialtile generator 1085 returns them to the tile processor 1050.

The loader/decompressor 1010 receives the multiplexed tile list 1035from the tile processor 1050 and handles the return of decompressedtiles 1045 to the tile processor 1050. In some embodiments, theloader/decompressor 1010 first checks one or more caches to determinewhether it has the requested tiles stored at the device on which themapping application operates. As shown, some embodiments include both afirst tile cache 1053 stored on non-volatile memory (e.g., disk, flashmemory, etc.) as well as a second tile cache 1054 stored in volatilememory (e.g., random access memory). When the loader/decompressor 1010finds the tiles in one of the caches 1053 and 1054, it sends these tilesback to the tile processor 1050 (for return to the requesting meshbuilder(s) 1015.

When the loader/decompressor 1010 does not have the tiles in its cache,it sends a request to the requestor 1005 for the remaining tiles. Uponreceiving these map tiles 1040 in a compressed format, theloader/decompressor decompresses the received tiles to generatedecompressed tiles 1045. In some embodiments, after generating the maptiles as described above, the mapping service also compresses the tilesusing an encoding technique. Different embodiments use differentencoding techniques. The loader/decompressor 1010 returns thesedecompressed tiles 1045 to the tile processor 1050, and in some casesalso stores them in one or both of the tile caches 1053 and 1054.

The requestor 1005, in some embodiments, receives requests for map tilesfrom the loader/decompressor 1010 (which in turn receives the requestsfrom the tile processor 1050). These map tiles, in some embodiments, arestored on a server (e.g., a server of the mapping service to which theuser's device connects). The requestor sends a tile list 1036 (receivedfrom the loader/decompressor 1010) that identifies the tiles needed fromthe mapping service (and not available in the tile caches 1053 and 1054.In some embodiments, the requestor takes advantage of the operatingdevice's network connections (e.g., a Wi-Fi connection, a GSMconnection, etc.) to contact the mapping service through the Internet toretrieve the needed map tiles. Upon receiving the tiles (in a compressedform) from the mapping service, the requestor 1005 returns thecompressed tiles 1040 to the loader/decompressor.

In some embodiments, the requestor 1005 (or the tile processor 1050, ora different portion of the pipeline) identifies tiles at additional zoomlevels that cover the same geographical area as the initially requestedtiles, and adds these tiles to the request list 1036 so that the tileswill be available if needed in the near future. In addition, someembodiments automatically request tiles at the same (or different zoomlevels) for nearby geographical regions, in order to have the tilesavailable in case the user pans the map. In some embodiments, therequestor 1005, loader/decompressor 1010, and tile processor 1050function as an independent portion of the processing pipeline, with themesh builders 1015 as the “clients” of this section.

The mesh builders 1015 (also referred to as tile sources) of someembodiments are instantiated by the tile provider 1020 in order to builddifferent layers of virtual map tiles. Depending on the type of mapbeing displayed by the mapping application, the tile provider 1020 mayinstantiate a different number and different types of mesh builders1015. For instance, for a satellite view map, the tile provider 1020might only instantiate one mesh builder 1015, as the satellite imagedoes not contain multiple layers of data. However, in some embodiments,additional mesh builders may be instantiated for generating thedifferent labels to overlay on the satellite images. For a 2D or 3Drendered vector map (i.e., a non-satellite image map), some embodimentsinstantiate separate mesh builders 1015 to build meshes for landcoverpolygon data (e.g., parks, bodies of water, etc.), roads, place ofinterest markers, point labels (e.g., labels for parks, etc.), roadlabels, traffic (if displaying traffic), buildings, raster data (forcertain objects at certain zoom levels), as well as other layers of datato incorporate into the map.

The mesh builders 1015 of some embodiments, receive “empty” virtual maptiles 1060 from the tile provider 1020 and return “built” virtual maptiles 1065 to the tile provider 1020. That is, the tile provider 1020sends to each of the mesh builders 1015 one or more virtual map tiles1060. Each of the virtual map tiles 1060 indicates an area of the worldfor which to draw a mesh. Upon receiving such a virtual map tile 1060, amesh builder 1015 identifies the map tiles needed from the mappingservice, and sends its list to the tile processor 1050.

Upon receiving the tiles back from tile processor 1050, the mesh builderuses vector data stored in the tiles to build a polygon mesh for thearea described by the virtual map tile. In some embodiments, the meshbuilder 1015 uses several different functions to build the mesh. Thesefunctions include the mesh generator 1016, the triangulator 1017, theshadow generator 1018, and the texture decoder 1019. In someembodiments, these functions (and additional mesh building functions)are available to each mesh builder, with different mesh builders 1015using different functions. For instance, the mesh builder responsiblefor the buildings layer may use a mesh generator 1016 and a triangulator1017. In addition, several different types of shadow generators may beavailable to the mesh builder 1015, including a first shadow generatorfor creating dynamic shadows (that change as the map rotates) and asecond shadow generator for creating a raster image drop shadow.

The mesh generator 1016 generates a mesh of vertices using the tilevector data, in some embodiments. The triangulator 1017 generatestriangles from the mesh, to simplify the eventual rendering. The shadowgenerator 1018 adds shadows to the mesh (e.g., by labeling verticesand/or polygons with values indicating to the renderer to draw a shadow,or how dark of a shadow to draw. The texture decoder 1019 decodestexture information (e.g., from a stylesheet) and applies the textureinformation to the mesh. In different embodiments, the textureinformation may indicate colors, patterns, etc. to add to the polygonswhen rendered, which is encoded into the mesh.

In some embodiments, the texture information may be determined based onstylesheet data 1055. Furthermore, some embodiments also use thisstylesheet data 1055 to determine the shadow, triangulation, and or meshconstruction data. Using stylesheet-driven rendering enables simplemodification to many aspects of the map output, because changes to atexture, color, etc. can be made through a minor modification of astylesheet. As a result, textures can be dynamically created on the fly.An example benefit of the stylesheet-driven rendering is thefacilitation of using different textures for certain types of objects atdifferent zoom levels or geographic regions. For instance, when viewedat a low zoom level (less detail), some embodiments might color a park asimple light green. On the other hand, as the user zooms in to a higherzoom level (more detail), the stylesheets indicate to apply a pattern(e.g., a foliage pattern) to the park region. Similarly, patterns athigher zoom levels could be added to buildings, bodies of water,asphalt, urban land cover, etc. This information can be coded into astylesheet and then the mesh builder simply adds the appropriate textureinformation to a tile mesh based on the zoom level of the tile.

By tagging roads (e.g., as urban, suburban, or rural), the mappingservice can induce the client application to use different textures forthe land cover regions around those roads. In addition, land coverregion tags can be updated by the server based on metrics indicative ofthe sort of area covered by the land cover region. For instance, someembodiments (on the mapping service end) determine the density of mobiledevices within the region (e.g., based on the number of devicesaccessing the mapping service) and generate tags for the land cover. Thestylesheets stored by the client devices (which may be updated from themapping service, in some embodiments) then indicate how to draw theseland cover regions. Similarly, different styles can be used forrendering aspects of different regions (e.g., desert, forest, rocky,etc. for land cover; different colors for labels in different states; orother such distinctions).

Each mesh builder 1015 returns its virtual map tiles 1065 to the tileprovider 1020 with its layer of the mesh filled in. The tile provider1020 receives from the controller 1075 a particular view (i.e., avolume, or viewing frustum) that represents the map view to be displayed(i.e., the volume visible from the virtual camera 1080). The tileprovider performs any culling (e.g., removing surface area too far away,removing objects that will be entirely behind other objects, etc.) insome embodiments, then sends the virtual map tiles 1060 to the meshbuilders 1015.

In some embodiments, the tile provider 1020 receives the built virtualmap tiles 1065 from the different mesh builders at different times(e.g., due to different processing times to complete more and lesscomplicated meshes, different time elapsed before receiving thenecessary map tiles from the tile processor 1050, etc.). Once all of thelayers of virtual map tiles have been returned, the tile provider 1020of some embodiments puts the layers together and releases the data tothe controller 1075 for rendering.

In some embodiments, the tile provider 1020 may have already received anew camera volume for which to build a mesh before the mesh buildershave returned their data. For instance, when the user quickly pans orzooms a map, the data returned by the mesh builders may be out of date.In some embodiments, the tile provider either drops the built virtualmap tile layers or stores them in memory. Whether to drop the builtvirtual map tiles depends, in different embodiments, on whether it islikely the built tiles will be needed soon (e.g., how much the user hasmoved the virtual camera, whether a navigation is running that makes itunlikely the application will display the older data) and the amount ofmemory currently in use.

The virtual camera 1080 generates a volume or surface for the pipeline1000 to render, and sends this information to the controller 1075. Basedon a particular location and orientation from which the map will berendered (i.e., the point in 3D space from which the user “views” themap), the virtual camera identifies a field of view to actually send tothe tile provider 1020. In some embodiments, when the mappingapplication is rendering the 3D perspective view for navigation, thefield of view of the virtual camera is determined according to analgorithm that generates a new virtual camera location and orientationat regular intervals based on the movement of the user device.

The controller 1075 is responsible for managing the tile provider 1020,virtual camera 1080, and map rendering engine 1025 in some embodiments.In some embodiments, multiple tile providers may actually beinstantiated, and the controller puts together several virtual map tiles(e.g., map tiles and building tiles) to create a scene that is handedoff to the map rendering engine 1025.

The map rendering engine 1025 is responsible for generating a drawing tooutput to a display device based on the mesh tiles 1065 sent from thevirtual camera. As shown, the map rendering engine 1025 of someembodiments has several sub-processes. In some embodiments, eachdifferent element is rendered by a different sub-process, with therendering engine 1025 handling the occlusion of different layers ofobjects (e.g., placing labels above or behind different buildings,generating roads on top of land cover, etc. This figure illustrates aroad rendering process 1026, a building rendering process 1027, and alabel rendering process 1028. Examples of additional processes include avegetation rendering process, a raster traffic rendering process, araster road rendering process, a satellite rendering process, a polygonrendering process, a background raster rendering process, etc.

Each of the rendering processes includes a set of rendering parameters;illustrated are road parameters 1036, building parameters 1037, andlabel parameters 1038. In some embodiments, this data includesinformation on how to render the roads (e.g., shader information,textures to use for different types of roads, etc.).

In some embodiments, these sets of rendering parameters are generated atleast in part by a rendering engine preparation operation 1070. Therendering engine preparation operation 1070 includes a shader compiler1071 and a texture loader 1072, among other operations. The shadercompiler 1071 compiles shaders that the rendering engine will use, andthe texture loader 1072 loads texture information (e.g., into therendering parameters). This texture information may come from thestylesheet data 1055 in some embodiments.

The operation of the rendering pipeline 1000 in some embodiments willnow be described. Based on user input to view a particular map region ata particular zoom level, the virtual camera 1080 specifies a locationand orientation from which to view the map region, and sends thisviewing frustum, or volume, to the controller 1075. The controller 1075instantiates one or more tile providers. While one tile provider 1020 isshown in this figure, some embodiments allow the instantiation ofmultiple tile providers at once. For instance, some embodimentsinstantiate separate tile providers for building tiles and for maptiles.

The tile provider 1020 performs any culling necessary to generate anempty virtual map tile identifying regions of the map region for which amesh needs to be built, and sends the empty virtual map tiles 1060 tothe mesh builders 1015, which are instantiated for the different layersof the drawn map (e.g., roads, land cover, POI labels, etc.). The meshbuilders 1015 use a manifest received from the mapping service thatidentifies the different tiles available on the mapping service server(i.e., as nodes of a quadtree). The mesh builders 1015 request specificmap tiles from the tile processor 1050, which removes any duplicaterequests and sends a tile list 1035 to the loader/decompressor 1010.

The loader/decompressor 1010 determines whether the requested tiles arestored in the tile caches (either the non-volatile storage cache 1053 orthe volatile storage cache 1054), and returns any such tiles to the tileprocessor 1050 for distribution to the requesting mesh builders 1015.For any tiles not already stored locally, the loader/decompressor 1010sends a request to the requestor 1005, which sends tile list 1036 (apared-down version of tile list 1035) to a remote mapping serviceserver. The requestor 1005 receives from the mapping service, andforwards to the loader/decompressor 1010, the requested map tiles incompressed form 1040. The loader/decompressor 1010 decompresses (e.g.,decodes) these tiles, stores them in its cache(s), and sends thedecompressed tiles 1045 to the tile processor 1050 for return to themesh builders 1015.

When some of the tiles requested by the mesh builders 1015 are notavailable, the tile processor 1050 sends the geospatial tile generator1085 (1) a request to generate geospatial map tiles for the unavailablemap tiles and (2) a set of available tiles. The geospatial tilegenerator 1085 uses the data contained in the set of available tiles togenerate geospatial map tiles for the unavailable map tiles and thenreturns the generated tiles to the tile processor 1050.

Once a particular mesh builder 1015 has received its map tiles, itbegins using the vector data stored in the map tiles to build the meshfor the virtual map tiles sent from the tile provider 1020. Afterbuilding the mesh for its map layer, the mesh builder 1015 sends thebuilt virtual map tile 1065 back to the tile provider 1020. The tileprovider 1020 waits until it has received all of the virtual map tilesfrom the various mesh builders 1015, then layers these together andsends the completed virtual map tile to the controller 1075. Thecontroller stitches together the returned tiles from all of its tileproviders (e.g., a virtual map tile and a virtual building tile) andsends this scene to the rendering engine 1025. The map rendering engine1025 uses the information in the map tiles to draw the scene fordisplay.

The processing pipeline of some embodiments is further described inconcurrently filed U.S. patent application Ser. No. ______, withattorney docket number APLE.P0405, entitled “Rendering Maps”. U.S.patent application Ser. No. ______, with attorney docket numberAPLE.P0405, is incorporated herein by reference.

III. Electronic System

Many of the above-described features and applications are implemented assoftware processes that are specified as a set of instructions recordedon a computer readable storage medium (also referred to as computerreadable medium). When these instructions are executed by one or morecomputational or processing unit(s) (e.g., one or more processors, coresof processors, or other processing units), they cause the processingunit(s) to perform the actions indicated in the instructions. Examplesof computer readable media include, but are not limited to, CD-ROMs,flash drives, random access memory (RAM) chips, hard drives, erasableprogrammable read-only memories (EPROMs), electrically erasableprogrammable read-only memories (EEPROMs), etc. The computer readablemedia does not include carrier waves and electronic signals passingwirelessly or over wired connections.

In this specification, the term “software” is meant to include firmwareresiding in read-only memory or applications stored in magnetic storagewhich can be read into memory for processing by a processor. Also, insome embodiments, multiple software inventions can be implemented assub-parts of a larger program while remaining distinct softwareinventions. In some embodiments, multiple software inventions can alsobe implemented as separate programs. Finally, any combination ofseparate programs that together implement a software invention describedhere is within the scope of the invention. In some embodiments, thesoftware programs, when installed to operate on one or more electronicsystems, define one or more specific machine implementations thatexecute and perform the operations of the software programs.

A. Mobile Device

The mapping and navigation applications of some embodiments operate onmobile devices, such as smart phones (e.g., iPhones®) and tablets (e.g.,iPads®). FIG. 11 is an example of an architecture 1100 of such a mobilecomputing device. Examples of mobile computing devices includesmartphones, tablets, laptops, etc. As shown, the mobile computingdevice 1100 includes one or more processing units 1105, a memoryinterface 1110 and a peripherals interface 1115.

The peripherals interface 1115 is coupled to various sensors andsubsystems, including a camera subsystem 1120, a wireless communicationsubsystem(s) 1125, an audio subsystem 1130, an I/O subsystem 1135, etc.The peripherals interface 1115 enables communication between theprocessing units 1105 and various peripherals. For example, anorientation sensor 1145 (e.g., a gyroscope) and an acceleration sensor1150 (e.g., an accelerometer) are coupled to the peripherals interface1115 to facilitate orientation and acceleration functions.

The camera subsystem 1120 is coupled to one or more optical sensors 1140(e.g., a charged coupled device (CCD) optical sensor, a complementarymetal-oxide-semiconductor (CMOS) optical sensor, etc.). The camerasubsystem 1120 coupled with the optical sensors 1140 facilitates camerafunctions, such as image and/or video data capturing. The wirelesscommunication subsystem 1125 serves to facilitate communicationfunctions. In some embodiments, the wireless communication subsystem1125 includes radio frequency receivers and transmitters, and opticalreceivers and transmitters (not shown in FIG. 11). These receivers andtransmitters of some embodiments are implemented to operate over one ormore communication networks such as a GSM network, a Wi-Fi network, aBluetooth network, etc. The audio subsystem 1130 is coupled to a speakerto output audio (e.g., to output voice navigation instructions).Additionally, the audio subsystem 1130 is coupled to a microphone tofacilitate voice-enabled functions, such as voice recognition (e.g., forsearching), digital recording, etc.

The I/O subsystem 1135 involves the transfer between input/outputperipheral devices, such as a display, a touch screen, etc., and thedata bus of the processing units 1105 through the peripherals interface1115. The I/O subsystem 1135 includes a touch-screen controller 1155 andother input controllers 1160 to facilitate the transfer betweeninput/output peripheral devices and the data bus of the processing units1105. As shown, the touch-screen controller 1155 is coupled to a touchscreen 1165. The touch-screen controller 1155 detects contact andmovement on the touch screen 1165 using any of multiple touchsensitivity technologies. The other input controllers 1160 are coupledto other input/control devices, such as one or more buttons. Someembodiments include a near-touch sensitive screen and a correspondingcontroller that can detect near-touch interactions instead of or inaddition to touch interactions.

The memory interface 1110 is coupled to memory 1170. In someembodiments, the memory 1170 includes volatile memory (e.g., high-speedrandom access memory), non-volatile memory (e.g., flash memory), acombination of volatile and non-volatile memory, and/or any other typeof memory. As illustrated in FIG. 11, the memory 1170 stores anoperating system (OS) 1172. The OS 1172 includes instructions forhandling basic system services and for performing hardware dependenttasks.

The memory 1170 also includes communication instructions 1174 tofacilitate communicating with one or more additional devices; graphicaluser interface instructions 1176 to facilitate graphic user interfaceprocessing; image processing instructions 1178 to facilitateimage-related processing and functions; input processing instructions1180 to facilitate input-related (e.g., touch input) processes andfunctions; audio processing instructions 1182 to facilitateaudio-related processes and functions; and camera instructions 1184 tofacilitate camera-related processes and functions. The instructionsdescribed above are merely exemplary and the memory 1170 includesadditional and/or other instructions in some embodiments. For instance,the memory for a smartphone may include phone instructions to facilitatephone-related processes and functions. Additionally, the memory mayinclude instructions for a mapping and navigation application as well asother applications. The above-identified instructions need not beimplemented as separate software programs or modules. Various functionsof the mobile computing device can be implemented in hardware and/or insoftware, including in one or more signal processing and/or applicationspecific integrated circuits.

While the components illustrated in FIG. 11 are shown as separatecomponents, one of ordinary skill in the art will recognize that two ormore components may be integrated into one or more integrated circuits.In addition, two or more components may be coupled together by one ormore communication buses or signal lines. Also, while many of thefunctions have been described as being performed by one component, oneof ordinary skill in the art will realize that the functions describedwith respect to FIG. 11 may be split into two or more integratedcircuits.

B. Computer System

FIG. 12 conceptually illustrates another example of an electronic system1200 with which some embodiments of the invention are implemented. Theelectronic system 1200 may be a computer (e.g., a desktop computer,personal computer, tablet computer, etc.), phone, PDA, or any other sortof electronic or computing device. Such an electronic system includesvarious types of computer readable media and interfaces for variousother types of computer readable media. Electronic system 1200 includesa bus 1205, processing unit(s) 1210, a graphics processing unit (GPU)1215, a system memory 1220, a network 1225, a read-only memory 1230, apermanent storage device 1235, input devices 1240, and output devices1245.

The bus 1205 collectively represents all system, peripheral, and chipsetbuses that communicatively connect the numerous internal devices of theelectronic system 1200. For instance, the bus 1205 communicativelyconnects the processing unit(s) 1210 with the read-only memory 1230, theGPU 1215, the system memory 1220, and the permanent storage device 1235.

From these various memory units, the processing unit(s) 1210 retrievesinstructions to execute and data to process in order to execute theprocesses of the invention. The processing unit(s) may be a singleprocessor or a multi-core processor in different embodiments. Someinstructions are passed to and executed by the GPU 1215. The GPU 1215can offload various computations or complement the image processingprovided by the processing unit(s) 1210. In some embodiments, suchfunctionality can be provided using CoreImage's kernel shading language.

The read-only-memory (ROM) 1230 stores static data and instructions thatare needed by the processing unit(s) 1210 and other modules of theelectronic system. The permanent storage device 1235, on the other hand,is a read-and-write memory device. This device is a non-volatile memoryunit that stores instructions and data even when the electronic system1200 is off. Some embodiments of the invention use a mass-storage device(such as a magnetic or optical disk and its corresponding disk drive,integrated flash memory) as the permanent storage device 1235.

Other embodiments use a removable storage device (such as a floppy disk,flash memory device, etc., and its corresponding drive) as the permanentstorage device. Like the permanent storage device 1235, the systemmemory 1220 is a read-and-write memory device. However, unlike storagedevice 1235, the system memory 1220 is a volatile read-and-write memory,such a random access memory. The system memory 1220 stores some of theinstructions and data that the processor needs at runtime. In someembodiments, the invention's processes are stored in the system memory1220, the permanent storage device 1235, and/or the read-only memory1230. From these various memory units, the processing unit(s) 1210retrieves instructions to execute and data to process in order toexecute the processes of some embodiments.

The bus 1205 also connects to the input and output devices 1240 and1245. The input devices 1240 enable the user to communicate informationand select commands to the electronic system. The input devices 1240include alphanumeric keyboards and pointing devices (also called “cursorcontrol devices”), cameras (e.g., webcams), microphones or similardevices for receiving voice commands, etc. The output devices 1245display images generated by the electronic system or otherwise outputdata. The output devices 1245 include printers and display devices, suchas cathode ray tubes (CRT) or liquid crystal displays (LCD), as well asspeakers or similar audio output devices. Some embodiments includedevices such as a touchscreen that function as both input and outputdevices.

Finally, as shown in FIG. 12, bus 1205 also couples electronic system1200 to a network 1225 through a network adapter (not shown). In thismanner, the computer can be a part of a network of computers (such as alocal area network (“LAN”), a wide area network (“WAN”), or an Intranet,or a network of networks, such as the Internet. Any or all components ofelectronic system 1200 may be used in conjunction with the invention.

Some embodiments include electronic components, such as microprocessors,storage and memory that store computer program instructions in amachine-readable or computer-readable medium (alternatively referred toas computer-readable storage media, machine-readable media, ormachine-readable storage media). Some examples of such computer-readablemedia include RAM, ROM, read-only compact discs (CD-ROM), recordablecompact discs (CD-R), rewritable compact discs (CD-RW), read-onlydigital versatile discs (e.g., DVD-ROM, dual-layer DVD-ROM), a varietyof recordable/rewritable DVDs (e.g., DVD-RAM, DVD-RW, DVD+RW, etc.),flash memory (e.g., SD cards, mini-SD cards, micro-SD cards, etc.),magnetic and/or solid state hard drives, read-only and recordableBlu-Ray® discs, ultra density optical discs, any other optical ormagnetic media, and floppy disks. The computer-readable media may storea computer program that is executable by at least one processing unitand includes sets of instructions for performing various operations.Examples of computer programs or computer code include machine code,such as is produced by a compiler, and files including higher-level codethat are executed by a computer, an electronic component, or amicroprocessor using an interpreter.

While the above discussion primarily refers to microprocessor ormulti-core processors that execute software, some embodiments areperformed by one or more integrated circuits, such as applicationspecific integrated circuits (ASICs) or field programmable gate arrays(FPGAs). In some embodiments, such integrated circuits executeinstructions that are stored on the circuit itself. In addition, someembodiments execute software stored in programmable logic devices(PLDs), ROM, or RAM devices.

As used in this specification and any claims of this application, theterms “computer”, “server”, “processor”, and “memory” all refer toelectronic or other technological devices. These terms exclude people orgroups of people. For the purposes of the specification, the termsdisplay or displaying means displaying on an electronic device. As usedin this specification and any claims of this application, the terms“computer readable medium,” “computer readable media,” and “machinereadable medium” are entirely restricted to tangible, physical objectsthat store information in a form that is readable by a computer. Theseterms exclude any wireless signals, wired download signals, and anyother ephemeral signals.

IV. Map Service Environment

Various embodiments may operate within a map service operatingenvironment. FIG. 13 illustrates a map service operating environment,according to some embodiments. A map service 1330 (also referred to asmapping service) may provide map services for one or more client devices1302 a-1302 c in communication with the map service 1330 through variouscommunication methods and protocols. A map service 1330 in someembodiments provides map information and other map-related data, such astwo-dimensional map image data (e.g., aerial view of roads utilizingsatellite imagery), three-dimensional map image data (e.g., traversablemap with three-dimensional features, such as buildings), route anddirection calculation (e.g., ferry route calculations or directionsbetween two points for a pedestrian), real-time navigation data (e.g.,turn-by-turn visual navigation data in two or three dimensions),location data (e.g., where is the client device currently located), andother geographic data (e.g., wireless network coverage, weather, trafficinformation, or nearby points-of-interest). In various embodiments, themap service data may include localized labels for different countries orregions; localized labels may be utilized to present map labels (e.g.,street names, city names, points of interest) in different languages onclient devices. Client devices 1302 a-1302 c may utilize these mapservices by obtaining map service data. Client devices 1302 a-1302 c mayimplement various techniques to process map service data. Client devices1302 a-1302 c may then provide map services to various entities,including, but not limited to, users, internal software or hardwaremodules, and/or other systems or devices external to the client devices1302 a-1302 c.

In some embodiments, a map service is implemented by one or more nodesin a distributed computing system. Each node may be assigned one or moreservices or components of a map service. Some nodes may be assigned thesame map service or component of a map service. A load balancing node insome embodiments distributes access or requests to other nodes within amap service. In some embodiments a map service is implemented as asingle system, such as a single server. Different modules or hardwaredevices within a server may implement one or more of the variousservices provided by a map service.

A map service in some embodiments provides map services by generatingmap service data in various formats. In some embodiments, one format ofmap service data is map image data. Map image data provides image datato a client device so that the client device may process the image data(e.g., rendering and/or displaying the image data as a two-dimensionalor three-dimensional map). Map image data, whether in two or threedimensions, may specify one or more map tiles. A map tile may be aportion of a larger map image. Assembling together the map tiles of amap produces the original map. Tiles may be generated from map imagedata, routing or navigation data, or any other map service data. In someembodiments map tiles are raster-based map tiles, with tile sizesranging from any size both larger and smaller than a commonly-used 256pixel by 256 pixel tile. Raster-based map tiles may be encoded in anynumber of standard digital image representations including, but notlimited to, Bitmap (.bmp), Graphics Interchange Format (.gif), JointPhotographic Experts Group (.jpg, .jpeg, etc.), Portable NetworksGraphic (.png), or Tagged Image File Format (.tiff). In someembodiments, map tiles are vector-based map tiles, encoded using vectorgraphics, including, but not limited to, Scalable Vector Graphics (.svg)or a Drawing File (.drw). Some embodiments also include tiles with acombination of vector and raster data. Metadata or other informationpertaining to the map tile may also be included within or along with amap tile, providing further map service data to a client device. Invarious embodiments, a map tile is encoded for transport utilizingvarious standards and/or protocols.

In various embodiments, map tiles may be constructed from image data ofdifferent resolutions depending on zoom level. For instance, for lowzoom level (e.g., world or globe view), the resolution of map or imagedata need not be as high relative to the resolution at a high zoom level(e.g., city or street level). For example, when in a globe view, theremay be no need to render street level artifacts as such objects would beso small as to be negligible in many cases.

A map service in some embodiments performs various techniques to analyzea map tile before encoding the tile for transport. This analysis mayoptimize map service performance for both client devices and a mapservice. In some embodiments map tiles are analyzed for complexity,according to vector-based graphic techniques, and constructed utilizingcomplex and non-complex layers. Map tiles may also be analyzed forcommon image data or patterns that may be rendered as image textures andconstructed by relying on image masks. In some embodiments, raster-basedimage data in a map tile contains certain mask values, which areassociated with one or more textures. Some embodiments also analyze maptiles for specified features that may be associated with certain mapstyles that contain style identifiers.

Other map services generate map service data relying upon various dataformats separate from a map tile in some embodiments. For instance, mapservices that provide location data may utilize data formats conformingto location service protocols, such as, but not limited to, RadioResource Location services Protocol (RRLP), TIA 801 for Code DivisionMultiple Access (CDMA), Radio Resource Control (RRC) position protocol,or LTE Positioning Protocol (LPP). Embodiments may also receive orrequest data from client devices identifying device capabilities orattributes (e.g., hardware specifications or operating system version)or communication capabilities (e.g., device communication bandwidth asdetermined by wireless signal strength or wire or wireless networktype).

A map service may obtain map service data from internal or externalsources. For example, satellite imagery used in map image data may beobtained from external services, or internal systems, storage devices,or nodes. Other examples may include, but are not limited to, GPSassistance servers, wireless network coverage databases, business orpersonal directories, weather data, government information (e.g.,construction updates or road name changes), or traffic reports. Someembodiments of a map service may update map service data (e.g., wirelessnetwork coverage) for analyzing future requests from client devices.

Various embodiments of a map service may respond to client devicerequests for map services. These requests may be a request for aspecific map or portion of a map. Some embodiments format requests for amap as requests for certain map tiles. In some embodiments, requestsalso supply the map service with starting locations (or currentlocations) and destination locations for a route calculation. A clientdevice may also request map service rendering information, such as maptextures or style sheets. In at least some embodiments, requests arealso one of a series of requests implementing turn-by-turn navigation.Requests for other geographic data may include, but are not limited to,current location, wireless network coverage, weather, trafficinformation, or nearby points-of-interest.

A map service, in some embodiments, analyzes client device requests tooptimize a device or map service operation. For instance, a map servicemay recognize that the location of a client device is in an area of poorcommunications (e.g., weak wireless signal) and send more map servicedata to supply a client device in the event of loss in communication orsend instructions to utilize different client hardware (e.g.,orientation sensors) or software (e.g., utilize wireless locationservices or Wi-Fi positioning instead of GPS-based services). In anotherexample, a map service may analyze a client device request forvector-based map image data and determine that raster-based map databetter optimizes the map image data according to the image's complexity.Embodiments of other map services may perform similar analysis on clientdevice requests and as such the above examples are not intended to belimiting.

Various embodiments of client devices (e.g., client devices 1302 a-1302c) are implemented on different portable-multifunction device types.Client devices 1302 a-1302 c utilize map service 1330 through variouscommunication methods and protocols. In some embodiments, client devices1302 a-1302 c obtain map service data from map service 1330. Clientdevices 1302 a-1302 c request or receive map service data. Clientdevices 1302 a-1302 c then process map service data (e.g., render and/ordisplay the data) and may send the data to another software or hardwaremodule on the device or to an external device or system.

A client device, according to some embodiments, implements techniques torender and/or display maps. These maps may be requested or received invarious formats, such as map tiles described above. A client device mayrender a map in two-dimensional or three-dimensional views. Someembodiments of a client device display a rendered map and allow a user,system, or device providing input to manipulate a virtual camera in themap, changing the map display according to the virtual camera'sposition, orientation, and field-of-view. Various forms and inputdevices are implemented to manipulate a virtual camera. In someembodiments, touch input, through certain single or combination gestures(e.g., touch-and-hold or a swipe) manipulates the virtual camera. Otherembodiments allow manipulation of the device's physical location tomanipulate a virtual camera. For instance, a client device may be tiltedup from its current position to manipulate the virtual camera to rotateup. In another example, a client device may be tilted forward from itscurrent position to move the virtual camera forward. Other input devicesto the client device may be implemented including, but not limited to,auditory input (e.g., spoken words), a physical keyboard, mouse, and/ora joystick.

Some embodiments provide various visual feedback to virtual cameramanipulations, such as displaying an animation of possible virtualcamera manipulations when transitioning from two-dimensional map viewsto three-dimensional map views. Some embodiments also allow input toselect a map feature or object (e.g., a building) and highlight theobject, producing a blur effect that maintains the virtual camera'sperception of three-dimensional space.

In some embodiments, a client device implements a navigation system(e.g., turn-by-turn navigation). A navigation system provides directionsor route information, which may be displayed to a user. Some embodimentsof a client device request directions or a route calculation from a mapservice. A client device may receive map image data and route data froma map service. In some embodiments, a client device implements aturn-by-turn navigation system, which provides real-time route anddirection information based upon location information and routeinformation received from a map service and/or other location system,such as Global Positioning Satellite (GPS). A client device may displaymap image data that reflects the current location of the client deviceand update the map image data in real-time. A navigation system mayprovide auditory or visual directions to follow a certain route.

A virtual camera is implemented to manipulate navigation map dataaccording to some embodiments. Some embodiments of client devices allowthe device to adjust the virtual camera display orientation to biastoward the route destination. Some embodiments also allow virtual camerato navigation turns simulating the inertial motion of the virtualcamera.

Client devices implement various techniques to utilize map service datafrom map service. Some embodiments implement some techniques to optimizerendering of two-dimensional and three-dimensional map image data. Insome embodiments, a client device locally stores rendering information.For instance, a client stores a style sheet which provides renderingdirections for image data containing style identifiers. In anotherexample, common image textures may be stored to decrease the amount ofmap image data transferred from a map service. Client devices indifferent embodiments implement various modeling techniques to rendertwo-dimensional and three-dimensional map image data, examples of whichinclude, but are not limited to: generating three-dimensional buildingsout of two-dimensional building footprint data; modeling two-dimensionaland three-dimensional map objects to determine the client devicecommunication environment; generating models to determine whether maplabels are seen from a certain virtual camera position; and generatingmodels to smooth transitions between map image data. Some embodiments ofclient devices also order or prioritize map service data in certaintechniques. For instance, a client device detects the motion or velocityof a virtual camera, which if exceeding certain threshold values,lower-detail image data is loaded and rendered of certain areas. Otherexamples include: rendering vector-based curves as a series of points,preloading map image data for areas of poor communication with a mapservice, adapting textures based on display zoom level, or rendering mapimage data according to complexity.

In some embodiments, client devices communicate utilizing various dataformats separate from a map tile. For instance, some client devicesimplement Assisted Global Positioning Satellites (A-GPS) and communicatewith location services that utilize data formats conforming to locationservice protocols, such as, but not limited to, Radio Resource Locationservices Protocol (RRLP), TIA 801 for Code Division Multiple Access(CDMA), Radio Resource Control (RRC) position protocol, or LTEPositioning Protocol (LPP). Client devices may also receive GPS signalsdirectly. Embodiments may also send data, with or without solicitationfrom a map service, identifying the client device's capabilities orattributes (e.g., hardware specifications or operating system version)or communication capabilities (e.g., device communication bandwidth asdetermined by wireless signal strength or wire or wireless networktype).

FIG. 13 illustrates one possible embodiment of an operating environment1300 for a map service 1330 and client devices 1302 a-1302 c. In someembodiments, devices 1302 a, 1302 b, and 1302 c communicate over one ormore wire or wireless networks 1310. For example, wireless network 1310,such as a cellular network, can communicate with a wide area network(WAN) 1320, such as the Internet, by use of gateway 1314. A gateway 1314in some embodiments provides a packet oriented mobile data service, suchas General Packet Radio Service (GPRS), or other mobile data serviceallowing wireless networks to transmit data to other networks, such aswide area network 1320. Likewise, access device 1312 (e.g., IEEE 802.11gwireless access device) provides communication access to WAN 1320.Devices 1302 a and 1302 b can be any portable electronic or computingdevice capable of communicating with a map service. Device 1302 c can beany non-portable electronic or computing device capable of communicatingwith a map service.

In some embodiments, both voice and data communications are establishedover wireless network 1310 and access device 1312. For instance, device1302 a can place and receive phone calls (e.g., using voice overInternet Protocol (VoIP) protocols), send and receive e-mail messages(e.g., using Simple Mail Transfer Protocol (SMTP) or Post OfficeProtocol 3 (POP3)), and retrieve electronic documents and/or streams,such as web pages, photographs, and videos, over wireless network 1310,gateway 1314, and WAN 1320 (e.g., using Transmission ControlProtocol/Internet Protocol (TCP/IP) or User Datagram Protocol (UDP)).Likewise, in some implementations, devices 1302 b and 1302 c can placeand receive phone calls, send and receive e-mail messages, and retrieveelectronic documents over access device 1312 and WAN 1320. In variousembodiments, any of the illustrated client device may communicate withmap service 1330 and/or other service(s) 1350 using a persistentconnection established in accordance with one or more securityprotocols, such as the Secure Sockets Layer (SSL) protocol or theTransport Layer Security (TLS) protocol.

Devices 1302 a and 1302 b can also establish communications by othermeans. For example, wireless device 1302 a can communicate with otherwireless devices (e.g., other devices 1302 b, cell phones, etc.) overthe wireless network 1310. Likewise devices 1302 a and 1302 b canestablish peer-to-peer communications 1340 (e.g., a personal areanetwork) by use of one or more communication subsystems, such asBluetooth® communication from Bluetooth Special Interest Group, Inc. ofKirkland, Wash. Device 1302 c can also establish peer to peercommunications with devices 1302 a or 1302 b (not shown). Othercommunication protocols and topologies can also be implemented. Devices1302 a and 1302 b may also receive Global Positioning Satellite (GPS)signals from GPS satellites 1360.

Devices 1302 a, 1302 b, and 1302 c can communicate with map service 1330over the one or more wire and/or wireless networks, 1310 or 1312. Forinstance, map service 1330 can provide a map service data to renderingdevices 1302 a, 1302 b, and 1302 c. Map service 1330 may alsocommunicate with other services 1350 to obtain data to implement mapservices. Map service 1330 and other services 1350 may also receive GPSsignals from GPS satellites 1360.

In various embodiments, map service 1330 and/or other service(s) 1350are configured to process search requests from any of client devices.Search requests may include but are not limited to queries for business,address, residential locations, points of interest, or some combinationthereof. Map service 1330 and/or other service(s) 1350 may be configuredto return results related to a variety of parameters including but notlimited to a location entered into an address bar or other text entryfield (including abbreviations and/or other shorthand notation), acurrent map view (e.g., user may be viewing one location on themultifunction device while residing in another location), currentlocation of the user (e.g., in cases where the current map view did notinclude search results), and the current route (if any). In variousembodiments, these parameters may affect the composition of the searchresults (and/or the ordering of the search results) based on differentpriority weightings. In various embodiments, the search results that arereturned may be a subset of results selected based on specific criteriainclude but not limited to a quantity of times the search result (e.g.,a particular point of interest) has been requested, a measure of qualityassociated with the search result (e.g., highest user or editorialreview rating), and/or the volume of reviews for the search results(e.g., the number of times the search result has been review or rated).

In various embodiments, map service 1330 and/or other service(s) 1350are configured to provide auto-complete search results that aredisplayed on the client device, such as within the mapping application.For instance, auto-complete search results may populate a portion of thescreen as the user enters one or more search keywords on themultifunction device. In some cases, this feature may save the user timeas the desired search result may be displayed before the user enters thefull search query. In various embodiments, the auto complete searchresults may be search results found by the client on the client device(e.g., bookmarks or contacts), search results found elsewhere (e.g.,from the Internet) by map service 1330 and/or other service(s) 1350,and/or some combination thereof. As is the case with commands, any ofthe search queries may be entered by the user via voice or throughtyping. The multifunction device may be configured to display searchresults graphically within any of the map display described herein. Forinstance, a pin or other graphical indicator may specify locations ofsearch results as points of interest. In various embodiments, responsiveto a user selection of one of these points of interest (e.g., a touchselection, such as a tap), the multifunction device is configured todisplay additional information about the selected point of interestincluding but not limited to ratings, reviews or review snippets, hoursof operation, store status (e.g., open for business, permanently closed,etc.), and/or images of a storefront for the point of interest. Invarious embodiments, any of this information may be displayed on agraphical information card that is displayed in response to the user'sselection of the point of interest.

In various embodiments, map service 1330 and/or other service(s) 1350provide one or more feedback mechanisms to receive feedback from clientdevices 1302 a-1302 c. For instance, client devices may provide feedbackon search results to map service 1330 and/or other service(s) 1350(e.g., feedback specifying ratings, reviews, temporary or permanentbusiness closures, errors etc.); this feedback may be used to updateinformation about points of interest in order to provide more accurateor more up-to-date search results in the future. In some embodiments,map service 1330 and/or other service(s) 1350 may provide testinginformation to the client device (e.g., an A/B test) to determine whichsearch results are best. For instance, at random intervals, the clientdevice may receive and present two search results to a user and allowthe user to indicate the best result. The client device may report thetest results to map service 1330 and/or other service(s) 1350 to improvefuture search results based on the chosen testing technique, such as anA/B test technique in which a baseline control sample is compared to avariety of single-variable test samples in order to improve results.

While the invention has been described with reference to numerousspecific details, one of ordinary skill in the art will recognize thatthe invention can be embodied in other specific forms without departingfrom the spirit of the invention. For instance, many of the figuresillustrate various touch gestures (e.g., swipe gestures, pinch gestures,spread gestures, etc.). However, many of the illustrated operationscould be performed via different touch gestures (e.g., a swipe insteadof a tap, etc.) or by non-touch input (e.g., using a cursor controller,a keyboard, a touchpad/trackpad, a near-touch sensitive screen, etc.).In addition, a number of the figures (including FIG. 9) conceptuallyillustrate processes. The specific operations of these processes may notbe performed in the exact order shown and described. The specificoperations may not be performed in one continuous series of operations,and different specific operations may be performed in differentembodiments. Furthermore, the process could be implemented using severalsub-processes, or as part of a larger macro process. Thus, one ofordinary skill in the art would understand that the invention is not tobe limited by the foregoing illustrative details, but rather is to bedefined by the appended claims.

We claim,:
 1. A non-transitory machine-readable medium storing a mappingapplication which when executed on a device by at least one processingunit renders views of a three-dimensional (3D) map, the mappingapplication comprising sets of instructions for: requesting a first setof map tiles associated with a portion of the 3D map; in response to therequest, receiving a second set of map tiles associated with portion ofthe 3D map; identifying a third set of map tiles included in the firstset of map tiles but not included in the second set of map tiles; foreach map tile in the third set of map tiles, generating a replacementmap tile comprising geospatial data; and rendering the portion of the 3Dmap based on the second set of map tiles and the set of replacement maptiles.
 2. The non-transitory machine-readable medium of claim 1, whereinthe mapping application further comprises a set of instructions for:defining a virtual camera for identifying portions of the 3D map torender; requesting from the virtual camera a view of the 3D map torender; and in response to the request, receiving the portion of the 3Dmap to render.
 3. The non-transitory machine-readable medium of claim 1,wherein the mapping application further comprises a set of instructionsfor identifying distance information from a subset of the second set ofmap tiles, wherein the set of instructions for generating, for each maptile in the third set of map tiles, the replacement map tile comprises aset of instructions for generating the replacement map tile based on theidentified distance information.
 4. The non-transitory machine-readablemedium of claim 1, wherein the geospatial data comprises longitude andlatitude data.
 5. The non-transitory machine-readable medium of claim 1,wherein the geospatial data comprises data representing distances to anearest map tile in the second set of map tiles.
 6. The non-transitorymachine-readable medium of claim 1, wherein the geospatial datacomprises a scale that indicates a set of distances of the portion ofthe 3D map.
 7. The non-transitory machine-readable medium of claim 1,wherein the geospatial data comprises distances of a geographical regionby which the portion of the 3D map represents.
 8. A method for renderinga view of a three-dimensional (3D) map to display on a device, themethod comprising: receiving map data that describes a section of the 3Dmap to use to render the view of the 3D map; determining whether the mapdata is missing data for any areas of the section of the 3D map; whendata is not determined missing from the map data, rendering the view ofthe 3D map based on the map data; and when data is determined missingfrom the map data, rendering the view of the 3D map that includesgeospatial data derived from the map data in place of the areas of the3D map with missing map data.
 9. The method of claim 8 furthercomprising requesting the map data from a map data provider.
 10. Themethod of claim 9, wherein requesting the map data comprises sending tothe map data provider a list specifying the map data.
 11. The method ofclaim 9, wherein determining that data is missing from the map datacomprises determining that the map tile provider does provide the data.12. The method of claim 8, wherein determining that data is missing fromthe map data comprises determining that the data is not stored in astorage on the device for caching map data.
 13. The method of claim 8,wherein the map data includes building data and road data.
 14. Themethod of claim 8, wherein rendering the view of the 3D map thatincludes the geospatial data comprises identify a scale of the view ofthe 3D map based on a map coordinate system associated with the 3D map.15. The method of claim 8, wherein rendering the view of the 3D map thatincludes the geospatial data comprises identify a scale of the view ofthe 3D map based on distance information included in the received mapdata.
 16. A non-transitory machine-readable medium storing a programwhich when executed on a device by at least one processing unit rendersviews of a three-dimensional (3D) map, the program comprising sets ofinstructions for: displaying a first view of a three-dimensional (3D)map; in response to an operation to adjust the first view of the 3D map,rendering a second view of the 3D map that includes a set of sections ofthe 3D map replaced with geospatial information; and displaying thesecond view of the 3D map.
 17. The non-transitory machine-readablemedium of claim 16, wherein the set of instructions for rendering thesecond view of the 3D map comprises a set of instructions for generatingeach section in the set of sections of the 3D map based on othersections of the 3D map used to render the second view of the 3D map. 18.The non-transitory machine-readable medium of claim 17, wherein the setof instructions for rendering the second view of the 3D map furthercomprises a set of instructions for rendering the second view of the 3Dmap based on the generated set of sections of the 3D map
 19. Thenon-transitory machine-readable medium of claim 16, wherein the set ofinstructions for displaying the second view of the 3D map comprises aset of instructions for displaying a bolding around each section of theset of sections of the 3D map replaced with geospatial information. 20.The non-transitory machine-readable medium of claim 16, wherein theoperation to adjust the first view of the 3D map comprises panning the3D map.
 21. The non-transitory machine-readable medium of claim 16,wherein the operation to adjust the first view of the 3D map compriseszooming in on the 3D map.
 22. The non-transitory machine-readable mediumof claim 16, wherein the operation to adjust the first view of the 3Dmap comprises zooming out from the 3D map.
 23. The non-transitorymachine-readable medium of claim 16, wherein the operation to adjust thefirst view of the 3D map comprises zooming in on the 3D map.
 24. Thenon-transitory machine-readable medium of claim 16, wherein the set ofinstructions for displaying the second view of the 3D map comprises aset of instructions for displaying, in each section of the set ofsections of the 3D map, (1) a grid of perpendicular lines and (2)different distance indicators that indicate distances between differentsets of parallel lines in the grid of perpendicular lines.